AB129. Osteogenesis imperfecta: clinical features and bisphosphonate treatment outcome

Background and objective: Osteogenesis imperfecta (OI) comprises a group of disorders principally affecting type I collagen which result in increased bone fragility. Children with severe OI suffer recurrent fractures, resulting in severe deformity and growth stunting in many cases, with loss of independent ambulation by the teenage years in over 50% of cases. Recently, cyclical intravenous treatment with pamidronate has proven of benefit to children with severe forms of OI. This article aims to describle clinical features and laboratory manifestations of patient with OI and evaluate outcome of bisphosphonate management.

Methods: Clinical features, biochemical finding, and management outcome of 104 cases were study. The patients were classified into four major subtypes of Sillience et al. 1979. Patients with severe types were treatment with pamidronate (Aredia) used Rauch protocol 2003.

Results: Now we have 196 patients (87 females and 109 males) but we studied focus on 104 patients from 98 families (60 males, 44 females) onset at 2.1±3.0 years (median 0.35) with the average fracture bone of 5.9±4.4 times. In there, 17% type I, 8% type II, 63% type III, and 12% type IV. Clinical features include of intrauterine fracture visible on ultrasound 35%, bone deformation after birth 68%, triangle face 76%, long bone deformation 91%, chest deformation 46%, scoliosis 27%, short status 90%, blue sclera 83%, dentinogenesis imperfecta 20%, hearing loss 6%. Thirty patients have been treated with pamidronate at 3.2±3.7 years (4 months to 8 years) during 13±0.8 months (6-30 months). Fourteen patients had fracture bone after 6 months of treatment but no patients had fracture bone after 12 months. Seven patients had been treatment after 1.6±0.5 years, BMD increase from 0.39±0.311 to 0.79±0.105 g/cm² (P<0.05). One patient had fever reaction after first pamidronate infusion but controlled with standard antipyretic therapy, and do not recur in later treatments.

Conclusions: OI has seriously affected the life of the patients and bisphosphonate therapy has shown some real long-term promise in the treatment of young patients with OI. No significant side effects have been noted, which is of the utmost importance in therapy destined for children.

Keywords: Osteogenesis imperfecta (OI); bisphosphonate treatment